Civil Engineering Reference
In-Depth Information
Figure 6.
Thermograms of methylene blue complexes of illite-montmorillonite mixes.
[16]
2.2
Other Thermal Methods
Application of multiple thermal techniques to clay mineral identi-
fication and behavior is more advantageous than applying any single
technique.
Rai, et al.,
[17]
compared the relative merits in the use of DTA and
DTG techniques for single, binary, and ternary systems containing clay
minerals kaolinite, illite, nontronite, and monmorillonite. The techniques
were found to be equally useful for single systems. DTA enabled semi-
quantitative estimation of the heat values, DTG enabled a more accurate
estimation of the weight losses due to desorption and dehydroxylation. For
the binary systems, DTG was found to be more useful because it could
resolve dehydration peaks more clearly than the DTA technique. In the
DTG, the ternary systems showed three peaks for the dehydration, and,
thus, the presence of all the clay minerals. It was also concluded that the
dynamic weight loss values were slightly lower than those obtained by the
static method. DTA was very advantageous in providing information on the
exothermal effects.
